WO2019106699A1

WO2019106699A1 - Composition of cement applicable substantially in the building field and process for manufacturing it

Info

Publication number: WO2019106699A1
Application number: PCT/IT2017/000272
Authority: WO
Inventors: Claudio Pelusi
Original assignee: Claudio Pelusi
Priority date: 2017-11-30
Filing date: 2017-11-30
Publication date: 2019-06-06
Also published as: EP3717436A1; PE20201471A1

Abstract

The invention relates to a composition of cement, applicable substantially in the building field with the function of self-levelling screed both for internal and for external environments, with remarkable mechanical strength and with excellent quality of acoustic insulation and thermal conductivity, for the consecutive laying of tiles, parquet, linoleum, resin or equivalent materials, and it also relates to a process for manufacturing this composition of cement. There are described in detail all the used materials, that are mixed to each other, and the maximum and minimum quantities of the same materials, and their modality of mixing.

Description

“COMPOSITION OF CEMENT APPLICABLE SUBSTANTIALLY IN THE BUILDING FIELD

AND PROCESS FOR MANUFACTURING IT”

The invention relates to a composition of cement, applicable substantially in the building field with the function of self-levelling screed both for internal and for external environments, with remarkable mechanical strength and with excellent quality of acoustic insulation and thermal conductivity, for the consecutive laying of tiles, parquet, linoleum, resin or equivalent materials, and it also relates to a process for manufacturing this composition of cement.

There are known in the market pre-mixed self-levelling screeds, which are constituted by dried sands with pre-set compositions, by binder materials for building industry based of gypsum or specific additives materials of the traditional type. For using these types of self-levelling screeds, the workers must observe a set of very strict limits with regard to the preparation of the casting of the cementitious material.

Indeed, it is necessary that, during the first forty-eight hours since the casting of the cementitious material, such a casting is performed completely safe from the air flows of air of every type and coming from every direction, since, by using the gypsum as blowing agent into the screed, the presence of flows of air determines into the same screed, caused by well-known phenomenons of setting and of plastic shrinkage of the concrete casted in place, cracks and considerable damages that limits and sometimes may compromise the use of the same screed. For the above said reason, also, it is easily deducible that such cementitious compositions are not able to be used in external environments.

For preventing the presence of the flows of air during the casting of the self-levelling screed of cementitious material, it is necessary to close, by means of polyethylene sheets, all the openings (doors, windows and French windows) of the environment wherein such a casting is performed, and this operation is difficult to be realized in practice and requires always the availability of this closing material and the execution of further working phases, that involves considerable additional costs for the workers of the field. Furthermore, if the openings to be closed have remarkable dimensions, as for example in the case of shopping centres and buildings with many openings, it may be almost impossible to close the same openings, thereby impeding the use of such materials for self-levelling screeds to be poured in work.

Moreover, for preventing the arise of above-specified problems, these screeds have to be reinforced with electro-welded or galvanized metallic nets, that on the one hand they are needed to increase the bending strength, on the other hand they are problematic for the workability of the screed, wherein the thickness are generally very small.

Alternatively, for pouring other types of existing self-levelling screeds on the surface of a slab, it is necessary to extend previously polyethylene sheets on to the entire surface of the same slab, in such a way that the casting doesn’t break the slab.

For obtaining self-levelling screeds, actually, there also used compositions of cement applicable onto the floors of inhabited environments, which are constituted substantially by the combination and the mixing into water of a set on mainly components, as for example waste materials, binder materials of various kind for construction, and aerating additives.

Said waste materials are substantially constituted by the following elements and their derived products, previously ground into particles of reduced grain, waste of heterogeneous plastic materials, wastes of elastomeric materials (rubbers, etc...), municipal solid waste, wastes of wood of various type, aggregate materials for building industry of various kind, glass remainders of various kind, whereas said binder material for construction are substantially constituted by cement, limes, gypsum of various kind, epoxy resins, and/or acrylic resins, whereas said airing additives are substantially constituted by organic and inorganic surface-active substances, and are adapted to help the mixing and the wettability of the same composition.

The obtained composition is introduced into cement mixers of similar containers, and is pourable on to the floor by means of pumping through supply means, and it is also pourable into moulds or formworks for forming preformed panels with different shapes and dimensions, which are then applicable into the relative application positions.

The presence of the airing surface-active substances, adapted to increase the wettability of and to help the mixing of the composition of cement, during the mixing phase of the composition of cement, produce very damp air bubbles in a non-controllable quantity that, once the screed has been laid, they tend to go up, that is toward the upper surface of the same screed, therefore, during the plastic shrinkage of the composition, there is formed a body with a very stiff lower part and very fragile upper superficial part and subjected to cracks and/or exhaustion, so not perfect for the laying of any additional upper layer, as for example tails, parquet, ecc..

Furthermore, the stiffness of the lower part of the screed make this latter more fragile during the thermohygrometric deformations, by producing easily internal cracks and/or a swelling thereof in correspondence of the same cracks or the screed comers.

Finally, the presence of these very damp air bubbles causes that, for the complete drying of the screed for be able to perform the subsequent laying operations, it is needed to wait a time comprise from few month to one year.

The scope of the present invention is to realize a composition of cement that deletes all the above- described drawbacks.

This composition of cement and the process for manufacturing it are realized with the constructive characteristics substantially described, with particular reference to the attached patent claims.

The invention will better understand from the following description, given by way of a not limitative example only. In the present description it is described a composition of cement, applicable substantially in the building field with the function of self-levelling screed both the internal environments and external environments, with remarkable mechanic strength and with great acoustic insulation and thermic conductance qualities, for the subsequent lying of tiles, parquet, linoleum resin or equivalent materials, and it also relates to a process for manufacturing this composition of cement.

The composition of cement according to this invention is substantially constituted by the following main components mixed to each other, the quantities of which added to each other are always 100% of the final product :

a) a first component formed by at least one of the following waste materials of various kind, derived from industrial processing or recycle materials, ground into particles of reduced grain, in the order of an average from 2 to 20 mm on average : plastic materials of the heterogeneous type (i.e. coloured, light blue, transparent PET bottles, bottles neolithes, aggregates, PE, PP, LDPE, HDPE, EPS etc...), elastomeric materials (rubbers, etc...), polymeric plastic compositions (poly- coupled materials, etc...), paper, cardboard, wood and wooden essences of various kind , aggregate materials for building industry of various kind, glass.

The above-said materials are ground into grinding means of traditional type (grinder mills, etc...) into particles of reduced grain, in the order of from 2 to 20 mm on average, with subsequent homogeneous mixing of all the ground materials, by means of the use of mixing machines of the traditional type, thereby obtaining a mixture of these waste materials.

Such a first component a) is used in the quantity comprised between Kg. 0,1 and Kg. 4,5 for each Kg. 100,00 of finished product, according to the desired noise abatement and the thermal conductance ;

b) A second component, constituted by the materials that will be described and that are mixed with the above-said materials of various kind, described in the point a).

According to the invention, such a second component is constitute by the following materials :

- Concrete, both the Portland and the Pozzolanico type, adapted to act as binder of the composition ;

- Aggregates stones, that is fine sand of the calcareous or silica type ;

- Fluidizer and super-fluidizer additives per se known, adapted to improve the workability of the composition of cement and to reduce the use of water ;

- Aluminium powder, acting as blowing agent and so adapted to maintain controlled the production of air during the mixing and the processing of the composition of cement ;

- Hydroxypropyl cellulose having a viscosity comprised between mPas. 100 and 30.000, preferably between mPas. 5.000 and 15.000, and adapted to include the air bubbles formed during the mixing of the composition of cement, in such a way that the resulting screed be lighter and with a low elastic modulus, and that this produced air doesn’t go up toward the upper surface of the same screed, thereby preventing that such a upper surface is friable.

Thus, for suiprising effect, with the combination of the above-said aluminium powder and the Hydroxypropyl cellulose, as first effect it is obtained an effect of control of the homogeneous dispersion of the mass of the polymeric materials by conferring to it a function of joint rather than of fibres and so it is obtained also a controlled plastic shrinkage of the composition of cement during the plastic phase, by reducing considerably its settings and initial cracks.

Furthermore, during the first drying phase of the composition of cement, this latter is less stiff and therefore it may acquire controlled deformations and thermohygrometric variations without cracks of the obtained finished product, namely the screed.

The composition of cement is constituted by the materials of the two above-said component in the quantities comprised in the following limit- values, and it as already previously indicated with a total value of the 100% of finished product : first component from Kg. 0,100 to Kg. 4,50 for each Kg. 100,00 of finished product ; concrete : from Kg. 15,00 to Kg. 30,00 for each Kg. 100,00 of finished product ; fine sand : from Kg. 60,00 to Kg. 80,00 for each Kg. 100,00 of finished product ;

aluminium powder : from Kg. 0,005 to Kg. 1,00 for each Kg. 100,00 of finished product ;

Hydroxypropyl cellulose : from Kg. 0,030 to Kg. 3,00 for each Kg. 100,00 of finished product ; fluidizer and super-fluidizer additives : from Kg. 0,050 to kg. 3,50 for each Kg. 100,00 of finished product . To the first above-said first and second components, always for a total of 100% of finished product, it is possible to add one or more of the additional components, with the quantities that will be indicated :

- Third component : constituted by per se known filler, that for example may be constituted by finest siliceous sand, or by calcium carbonates, or by silica, hydrated lime, per se known super- fluidizer additives, such as for example the acrylic polymers (i.e. the Primium PC 20), the poly- carboxylates, the naphthalene polymers such as the naphthalen-sulphonated polymers, and the ligno-sulphonates polymers and further known polymers, and melaminic polymers, in quantity comprised in the following limit- values from Kg. 5,00 to Kg. 30,00 for each Kg. 100,00 of finished product, such a filler being adapted to regulate, when it is needed, the granulometric scale of the sand according to the component, namely by ensuring the stability of the mixture, and by increasing also the compressive strength of the composition of cement at finished product ;

- Fourth component : constituted by retarders of the per se known natural type in the form of powder, and adapted to be used when it is planned the kneading of the composition of cement, object of the present invention, in advance to the processing into construction site, as for example into the concrete mixing pant, in such a way to reduce the moisturization grade of the concrete during the first hours, in the case there aren’t sufficient the ftuidizer and super-fluidizer additives, namely by obtaining a mixture where it is produced an adsorption of the organic products onto the concrete, thereby preventing the moisturization of this latter and by allowing the process of the composition of cement also after various hours and therefore be able to perform a possible transportation, said fourth component being in a quantity from Kg. 0,030 to Kg. 3,00 for each Kg.

100,00 of finished product ;

- Fifth component : constituted by accelerators, constituted as for example by powder of calcium formate, and adapted to reduce the setting time of the composition of cement and to increase its mechanical strength, and so it is adapted to be mixed with the other components of the composition of cement directly on the working construction site, during climates with low temperatures, by accelerating the setting time of the concrete and/or subsequently the use of the above-said fourth component, in such a way that the concrete is moisturized and the setting time of the composition of cement is brought back to the starting state, said fifth component being in a quantity from Kg. 0,100 to Kg. 5,00 for each Kg. 100,00 of finished product.

The above-said components used for obtaining the desired composition of cement, are mixed with water, which is in a quantity comprised in the limit values from Kg. 10,00 and Kg. 30,00 for each Kg. 100,00 of finished product, according to the sand absorption.

The process for manufacturing the above-said composition of cement, object of the present invention, may consider that, the materials of the above-said first and second components, mixed in a homogenous manner to each other at the dried state, be introduced with the above specified quantities, into suitable per se known containers, as for example barrels, silos, bags or receptacles of various kind of the concrete mixing plants of the traditional type, that are then transported, at a dried state with the sole sand humidity, to construction site where there are present the inhabited buildings into which the foreseen works must be effected, where the water is then added with the above-specified quantities into suitable containers wherein there are contained said first and second components mixed to each other at the dried state, and the obtained mixture is further mixed by obtaining the composition of cement, object of the present invention.

In the case it is necessary to regulate the granulometric scale of the sand of the second component, namely by ensuring the stability of the mixture, and by increasing also the compression strength of the composition of cement at finished product, it is added the third component, with the above- specified quantities, to the above-said obtained mixture with said first and second components at the dried state, and the whole thing is then mixed with water, as the above described process.

In the case that working construction site is located in an area with a cold climate , and then it is necessary to reduce the setting time of the cement composition, the above said fifth component is added, with the above specified quantities, and the whole thing is then mixed with water, as by above described process.

Furthermore, such a process provides that, the materials of the above said first, second and possible third components may be also mixed together the fourth component and the water, with the above specified quantities, into above said suitable containers and with provide quantities, directly into the concrete mixing plants as already described and then transported to the working construction sites where the foreseen works must be effected, in such a way that the fourth component allows a delay of the setting of the composition of cement, making this latter workable also after various hours ; after, the fifth component is then added and mixed together the mixture obtained up to now, with the above specified quantities, in such a way that the setting time of the composition of cement be brought back at the starting state, namely by cancelling the effect of the fourth component since is no longer necessary.

The composition of cement obtained with one of the above said manners, is subsequently introduced into a mixing and delivering pump, or similar means, from which the same composition of cement is applied at work by being poured onto the floor and/or on to the walls and/or onto the floor foundations, for fonning the self-levelling screed, or in alternative from which said composition of cement may also be poured into moulding means (moulds, formworks, etc...), for forming preformed panels of forms, dimensions and different appearing, that are applicable subsequently in the relative installation positions.

Claims

1. Composition of cement, applicable substantially in the building field with the function of self- levelling screed with remarkable mechanic strength and with great acoustic insulation and thermic conductance qualities, for the subsequent lying of tiles, parquet, linoleum resin or equivalent materials, and comprises at least a first and second main components mixed to each other and with water into suitable containers before the pouring at work of the same composition of cement, whose quantities added to each other be always 100% of the finished product, wherein the first component is constituted by at least one the following waste materials of various kind, derived from industrial processing or recycle materials, ground into particles of reduced grain, in the order of an average from 2 to 20 mm on average : plastic materials of the heterogeneous type (i.e. coloured, light blue, transparent PET bottles, bottles neolithes, aggregates, PE, PP, LDPE, HDPE, EPS etc...), elastomeric materials (rubbers, etc...), polymeric plastic compositions (poly-coupled materials, etc...), paper, cardboard, wood and wooden essences of various kind , aggregate materials for building industry of various kind, glass, characterized in that said second component is constituted by the following materials :

- Concrete, both the Portland and the Pozzolanico type, adapted to act as binder of the composition;

- Aggregates stones, that is fine sand of the calcareous or silica type ;

- Elydroxypropyl cellulose having a viscosity comprised between mPas. 100 and 30.000, preferably between mPas. 5.000 and 15.000, and adapted to include the air bubbles fonned during the mixing of the composition of cement, in such a way that the resulting screed be lighter and with a low elastic modulus, and that this produced air doesn’t go up toward the upper surface of the same screed, thereby preventing that such a upper surface is friable, and for surprising effect, with the combination of the above-said aluminium powder and the Hydroxypropyl cellulose, as first effect it is obtained an effect of control of the homogeneous dispersion of the mass of the polymeric materials by conferring to it a function of joint rather than of fibres and so it is obtained also a controlled plastic shrinkage of the composition of cement during the plastic phase, by reducing considerably its settings and initial cracks, furthermore, during the first drying phase of the composition of cement, this latter is less stiff and therefore it may acquire controlled defonnations and thermohygrometric variations without cracks of the obtained finished product, namely the screed, said composition of cement being constituted by the materials of the two above-said component in the quantities comprised in the following limit- values, always with a maximum value of the 100% of finished product :

- first component from Kg. 0,100 to Kg. 4,50 for each Kg. 100,00 of finished product ;

- Second component :

concrete : from Kg. 15,00 to Kg. 30,00 for each Kg. 100,00 of finished product ; fine sand : from Kg. 60,00 to Kg. 80,00 for each Kg. 100,00 of finished product ; aluminium powder : from Kg. 0,005 to Kg. 1,00 for each Kg. 100,00 of finished product ; Hydroxypropyl cellulose : from Kg. 0,030 to Kg. 3,00 for each Kg. 100,00 of finished product ; fluidizer and super- fluidizer additives : from Kg. 0,050 to kg. 3,50 for each Kg. 100,00 of finished product ;

- water, which is in a quantity comprised in the limit values from Kg. 10,00 and Kg. 30,00 for each Kg. 100,00 of finished product, according to the sand absorption.

2. Composition of cement according to claim 1, characterized in that it comprises a further third component, which is constituted by per se known filler, that for example may be constituted by finest siliceous sand, or by calcium carbonates, or by silica, hydrated lime, per se known super- fluidizer additives, such as for example the acrylic polymers (i.e. the Primium PC 20), the poly- carboxylates, the naphthalene polymers such as the naphthalen-sulphonated polymers, and the ligno-sulphonates polymers and further known polymers, and melaminic polymers, in quantity comprised in the following limit- values from Kg. 5,00 to Kg. 30,00 for each Kg. 100,00 of finished product, such a filler being adapted to regulate, when it is needed, the granulometric scale of the sand according to the component, namely by ensuring the stability of the mixture, and by increasing also the compressive strength of the composition of cement at finished product.

3. Composition of cement according to one of previous claims, characterized in that it comprises a further fourth component, which is constituted by retarders of the per se known natural type in the form of powder, and adapted to be used when it is planned the kneading of the composition of cement, object of the present invention, in advance to the processing into construction site, as for example into the concrete mixing pant, in such a way to reduce the moisturization grade of the concrete during the first hours, in the case there aren’t sufficient the fluidizer and super-fluidizer additives, namely by obtaining a mixture where it is produced an adsorption of the organic products onto the concrete, thereby preventing the moisturization of this latter and by allowing the process of the composition of cement also after various hours and therefore be able to perfonn a possible transportation, said fourth component being in a quantity from Kg. 0,030 to Kg. 3,00 for each Kg. 100,00 of finished product.

4. Composition of cement according to one of previous claims, characterized in that it comprises a further fifth component, which is constituted by accelerators, as for example by powder of calcium formate, and is adapted to reduce the setting time of the composition of cement and to increase the mechanical strength of this latter, and so it is adapted to be mixed with the other components of the composition of cement directly on the working construction site, during climates with low temperatures, by accelerating the setting time of the concrete and/or subsequently the use of the above-said fourth component, in such a way that the concrete is moisturized and the setting time of the composition of cement is brought back to the starting state, said fifth component being in a quantity from Kg. 0,100 to Kg. 5,00 for each Kg. 100,00 of finished product.

5. Process for manufacturing above said composition of cement according to one of the previous claims, wherein the above said waste materials of the first component are ground into grinding means of traditional type (grinder mills, etc...) into particles of reduced grain, in the order of from 2 to 20 mm on average, with subsequent homogeneous mixing of all the ground materials, be means of the use of mixing machines of the traditional type, thereby obtaining a mixture of these waste materials, characterized in that said first and second components, mixed in a homogenous manner to each other at the dried state are introduced, with the above specified quantities, into suitable per se known containers, as for example barrels, silos, bags or receptacles of various kind of the concrete mixing plants of the traditional type, that are then transported, at a dried state with the sole sand humidity, to construction site where there are present the inhabited buildings into which the foreseen works must be effected, where the eventually lacking water is then added into suitable containers wherein there are contained said first and second components mixed to each other, and the obtained mixture is further mixed by obtaining the composition of cement, object of the present invention, which is subsequently introduced into a mixing and delivering pump, or similar means, from which the same composition of cement is applied at work by being poured onto the floor and/or on to the walls and/or onto the floor foundations, for forming the self-levelling screed, or in alternative from which said composition of cement may also be poured into moulding means (moulds, formworks, etc...), for forming preformed panels of forms, dimensions and different appearing, that are applicable subsequently in the relative installation positions.

6. Process according to claim 5, characterized in that the third component is added with the above-specified quantities to the obtained mixture with said first and second components, for the above described scopes.

7. Process according to claim 5 or 6, characterized in that, in the concrete mixing plant, the fourth component is added to and mixed with the other components mixed to each other, and then be mixed with water, with the above specified quantities, and for the above described scopes.

8. Process according to claim 5 or 6, characterized in that, at the working construction site, and in the case this latter be located in an area with a cold climate, the fifth component is added to and mixed with the previously component for being then mixed with the water, with the above specified quantities and for the above described scopes.